1. Field of the Invention
The present invention relates to a head of a plane or planing machine and, more particularly, to a plane head, which comprises a cylindrical base body including a plurality of stamped sheets arranged next to each other axially, a planing knife protruding radially beyond the surface of the base body from at least one longitudinal groove in the base body and fixed in the base body by a form-fitting connection or form-locking connection so that it cannot be radially dislodged or moved and at least one chuck wedge, which is received inside of a base body cavity formed by punched holes in the stamped sheets, whereby the planing knife is clamped in the base body by a centrifugal force during rotation of the plane head.
2. Prior Art
The known plane head of this kind, also called a knife carrier or planing shaft, described, for example, in German Patent Document DE 195 36 559 A1. This plane head is rotatably mounted in the housing of a hand-held planing machine driven by an electric motor. The chuck wedge is held non-releasably by only a spring (i.e. it cannot be dissembled without destroying the arrangement) inside of a cavity or recess in the base body of the plane head fixed elastically in it. This spring exerts a tension force on the planing knife, which is arranged in a longitudinal groove provided in the plane head when the plane head is idle, which prevents the planing knife from slipping out of the plane head. On rotation of the plane head the chuck wedge is forced outwardly, whereby its pressing force on the planing knife increases. A gripping slot formed in the chuck wedge, which cooperates with a projection formed on the base body, limits the radial motion of the chuck wedge toward the inside and toward the outside. The base body is formed by a punched packet of substantially identically shaped disks or identically shaped sheets, which are nonrotatably mounted on a plane head shaft and are axially clamped with each other by clamping bodies bearing on the shaft. A chuck wedge element and a leaf spring element are formed in each shaped sheet, so that the chuck wedge with a leaf spring attached elastically to the base body and with the chuck wedge result.
A similar planing head is known from European Patent Document EP 0 117 991 B1. The planing knife with a positioning groove formed in the knife front section engages a positioning stud extending axially, projecting into the groove side of the longitudinal groove. The positioning stud cooperates with the positioning groove to only prevent the planing knife from slipping out radially from the longitudinal groove. However radial play is provided which allows radial adjustment of the planing knife. A self-clamping chuck wedge with a small wedge angle of about 4 to 5.degree. forms the groove side bearing on the back of the planing knife and braces itself in the base body cavity or recess. For reliable self-clamping the chuck wedge must be made with a high degree of accuracy, which requires milling or grinding of the wedge pressing surfaces. The clamping of the planing knife occurs by brief activation of the hand-held planing machine, so that the planing knife is fixed in position by the self-chucking or self-clamping chuck wedge. For knife removal the chuck wedge must be given an inwardly directed blow with a hammer and soft metal piece so that it can then be withdrawn laterally with the knife from the longitudinal groove.